If you still use screen savers, Columbus-based developer M \ K Productions has a good one for you. Nintendo Saver 2015 fills your monitors with several NES games. Each one is actually a fully-functioning NES emulator playing a replay that was recorded in UberNES, and if you like, you can pick up a gamepad and take over control of one of the games on the spot. The recorded replays include my Super Mario Bros 3 playaround and a couple shorter videos showing glitches in Super Mario Bros 1 and Mega Man 2. If you like it, maybe I’ll record some more.
Source: http://www.ubernes.com/nesscreensaver.html via the UberNES – NES Screen Saver Facebook page